Following his discovery of the electron, JJ Thompson tried to explain matter as a purely electromagnetic phenomena. A paper by Searle, a colleague, in 1896 looked towards explaining inertia in purely electromagnetic terms. Challenged by this, after several years work, I completed my own theory in the summer of 19971. This explained how a spherical charge of no mass would resist acceleration. This theory was expressed in classical terms and showed how by assuming the substance of the magnetic field to be energy, it was possible to calculate the velocity with which magnetic flux emerged or sank back into the surface of a charge as it was accelerated. That movement generated an electric field which acted on the charge producing an inertial force proportional to the acceleration. The following year, I came across the work of Lorentz and Abraham. Both had derived similar theories, considering electrons moving at high velocity and predicting relativistic increases in mass. My theory was strictly classical, but unlike them, I had described the actual mechanism by which the inertial force is generated.
This paper combines ideas of Lorentz with my previous work to produce a theory explaining how inertial forces are generated and how these forces result in a relativistic increase in inertial mass. Conceptually, it takes us back to 1905 and the evolution of Lorentz-Poincare relativity into Einstein's SR. In this theory, the electron is assumed to have a definite velocity v against some background through which light travels at a constant speed. While personally preferring to identify that background as the presence of the electric fields of all charges2, this theory is consistent with an understanding of electromagnetism as described by the theory of relativity. In this context, v is the velocity of the charge in the observers inertial frame and the electric field of the charge and its surrounding magnetic field are the observed descriptors of its electromagnetic field as seen by that observer.
SI units are used throughout.